In the treatment of strand-shaped textile products it has been known to introduce the textile products in a closed treatment container, to connect their ends to each other to form a continuous material strand, and to start circulating said strand in a pre-specified direction of rotation, and to subject the circulating material strand to a treatment. Such treatment potentially includes subjecting the material strand to the action of an, in particular fluid, treatment agent (bath) and/or drying, tumbling, or otherwise treating the material strand in order to change the properties of the textile product, e.g., the hand, the plushness and the like. The circulating material strand may be driven by mechanical means, e.g., a winch; however, nowadays, as a rule, hydraulic or pneumatic drive systems are used, these systems operating in accordance with the Jet principle by using a Venturi transport nozzle, through which the material strand is being passed and which is charged with a liquid and/or gaseous transport medium, e.g., a bath, air, a steam/air mixture, inert gas and the like. An overview can be found, e.g., in: Dr. H. U. von der Elz, Ing. W. Christ, “Aerodynamic System for Dyeing Piece Goods,” International Textile Bulletin, Dyeing/Printing/Finishing 31 (1985), 3; pages 27-41).
Inasmuch as the strand length is considerably greater than the dimensions of the treatment container, the circulating material strand must be temporarily piled up on its circulation path. The piled up material strand package is received by a storage, in which the circulating material strand is continuously entered and from where the material strand is continuously removed on the opposite side.
For example, in high-temperature (HT) piece-dyeing machines comprising a treatment container configured as a pressure-proof, essentially cylindrical vat, the material storage is completely U-shaped with upward extending legs, whereby the material strand that is being continuously removed on the output side by a winch is passed through a Venturi transport nozzle and, along a transport section downstream of the transport nozzle, continuously entered into the storage. A pile-up device that piles up the material strand is interposed between the transport section and the material strand input into the storage. In such jet piece-dying machines utilizing the aerodynamic principle, liquid treatment agent is admixed either to the transport gas stream or is applied to the moving material strand in the region of the Venturi nozzle array. An example of such an apparatus utilizing the aerodynamic principle is described in EP 0 945 538.
An advantage of the explained jet treatment machines utilizing the aerodynamic principle is that they can be operated at a very low bath ratio (weight of the total bath (=treatment agent) in the container divided by the weight of the material strand to be treated). On the other hand, the textile product in the material package in the storage is exposed to a certain compressive force that is not expedient for certain textile products. Furthermore, the transport section and the material strand themselves introduce liquid treatment agent into the storage, said agent forming uncontrollable puddles and accumulations in the piled-up material package, said accumulations potentially impairing the treatment result and—in any event—requiring an increase of the number of circulations of the strand, in order to achieve a uniform treatment result, e.g., completely uniform dyeing.
In addition to the explained so-called short-term storage machines comprising a cylindrical treatment container and essentially U-shaped material storages, so-called long-term storage machines with bath circulation are used for certain textile products, i.e., machine systems utilizing the hydraulic principle, said machines being operated at a high bath ratio. An essential feature of these long-term storage machines is that their treatment container comprises an elongated, frequently essentially tubular, container part having a storage section for the accommodation of the piled up material strand and whose material strand output side is connected to a Venturi transport nozzle adjoined by a transport section leading to the material strand input side of the treatment container. In machines utilizing the hydraulic principle, the elongated, horizontally arranged storage section is more or less completely flooded with the bath, so that the piled up strand-shaped piece goods are almost in a floating state, with the result that no excessive influence of force on the material package occurs as it is passed through the material storage. An example of such a long-term storage machine utilizing the hydraulic principle is described in documents French Patent 2 778 417 and in DE Offenlegungsschrift 2 207 679, whereby, however, no separate material strand pile-up device is provided at the material storage input. The storage section of the treatment container in accordance with French Patent 2 778 417 comprises an essential straight sliding floor that is arranged at a distance above the container wall in a manner so as to descend from the material strand input side to the material strand output side. In these long-term storage machines comprising a predominantly horizontal treatment container with a small container diameter and with a transport section located below the treatment container, it is possible, as a rule, to achieve material strand velocities of 500 m/min that are employed in practical applications for a creaseless output of the strand-shaped piece goods.
From documents JP-753943 and JP-730505 long-term storage machines have been known, said machines utilizing—in order to drive the circulating material strand—an air/bath mixture or—for drying the material strand—only air, optionally air sucked in from the outside, said air acting on a nozzle element upstream of the transport section. The treatment container of these machines consists of a part that extends, at an angle greater than 45°, from the input side of the material strand steeply downward, said part being adjoined by an intermediate section that, at an angle smaller than 5°, also is inclined downward and that is connected at the material strand output end to a vertically upward extending part that leads to a head part holding the deflecting winch and from where the mentioned transport nozzle begins to extend. The transport nozzle is adjoined by a slightly downward inclined transport section leading to the steeply descending part of the transport container. The circulating material strand is automatically folded in pleats in the steeply descending part of the treatment container, whereby a denser, more compact material package results in the adjoining storage section that is inclined only gently by less than 5° with respect to the horizontal. These machines can operate at a very low bath ratio of up to 1:3 and less. However, the treatment agent accumulating in the transport section is introduced, together with the treatment agent carried along on the material strand, into the material storage, in which said agent drains from the compressed material package into a sump. This introduction of treatment agent into the storage in a hydraulic long-term storage machine is also described in EP 0 512 189 B1, in which a pile-up device adjoins the transport section perfused by treatment agent, said pile-up device performing an oscillating rotating movement about a stationary axis.